Catabolism of 2-deoxyglucose by phagocytic leukocytes in the presence of 12-O-tetradecanoyl phorbol-13-acetate.

Abstract

We have found that phagocytic leukocytes exposed to the tumor-promoting agent, 12-O-tetradecanoyl phorbol-13-acetate, efficiently release carbon-i of 2-deoxyglucose in the form of CO2 with concurrent intracellular accumulation of a phosphorylated 5-carbon intermediate. In the absence of 12-atetradecanoyl phorbol-13-acetate, these cells release barely detectable amounts of CO2 from 2-deoxyglucose. 12-0-Tetradecanoyl phorbol-13-acetate, at a concentration of 1 ng/ml, has an immedate effect on CO2 release, which is temperature-dependent and linear with time and cell number. The ability of a number of phorbol ester-like compounds to enhance this catabolic pathway for 2-deoxyglucose correlates with their ability to act as tumor promotors and inflammatory agents. Although this effect of phorbol esters appears to be restricted to granulocytes, monocytes, and macrop a es, the possibility arises that other mammalian cells are capable of catabolizing or can be induced to catabolize 2-deoxyglucose. Thus, 2-deoxyglucose decarboxylation should be considered whenever this analog of mannose and glucose is used as an indicator for sugar transport, especially when pharmacodynamic agents are present.12-O-Tetradecanoyl phorbol-1S-acetate (TPA), the most active tumor-promoting agent isolated from croton oil (1, 2), acts as an inflammatory agent (3), increases the level of proteases in mouse skin (4), and enhances the carcinogenicity of a number of agents applied to the skin (5). TPA is capable of evoking a multiplicity of changes in cultured cells which are generally considered to be characteristic of the transformed phenotype. Responses include an increase in plasminogen activator production (6-8), an increase in the rate of sugar transport (9), a decrease in LETS protein (10), altered morphology (11), and inhibition of terminal differentiation (12)(13)(14)(15)(16)(17).TPA also increases the rate of decarboxylation of glucose in human granulocytes via the hexose monophosphate shunt (18,19 fetal bovine serum. The human myeloid line HL-60 (22) was maintained in the same medium with a supplement of 20% heat-inactivated fetal bovine serum. For preparation of cell-free extracts, washed cells were suspended in 3 mM EDTA/30 ,uM NADP+/20 mM Hepes, pH 7.5, at a concentration of 107/ml. After three cycles of rapid freezing and thawing, particulate matter was removed by centrifugation at 15,000 rpm for 5 min. The supernatant contained all activity for NADP+-dependent CO2 release from glucose and 2-dGlc.Assay for Release of CO2. CO2 released by cells incubated under conditions described in figure and table captions was trapped in a Hyamine-soaked filter paper in a glass well suspended above the incubation mixture. The incubation was terminated by injection of concentrated sulfuric acid (100 ,ul/ml) and incubation was continued for 30 min at 37°C to ensure that all dissolved CO2 was released from the acidified medium. Radioactivity in the filter paper was determined in a scintillation counter with toluene-based fluor.Chromatographic Me...

2-Deoxyglucose Induces Noxa-Dependent Apoptosis in Alveolar Rhabdomyosarcoma

“…2-DG inhibits glycolysis and usage of glucose to produce ATP or fatty acids. However, 2-DG can be metabolized through the pentose phosphate pathway in some conditions (34), and a catalytic block does not sufficiently explain the toxicity of 2-DG (35). Moreover, 2-DG alters protein glycosylation in a manner that is different from that of glucose deprivation: While it inhibits N-glycosylation, it enhances O-GlcNAcylation.…”

12-O-Tetradecanoyl-Phorbol-13-Acetate Release of Glycosyltransferases from Human Blood Cells

“…; TPA, other phorbol derivatives, concanavalin A, dibutyryl-cAMP, dibutyryl-cGMP, 2-glycerol-phosphate, puromycin, phenobarbital, and fetuin were obtained from Sigma Chemical Co., St. Louis, Mo. ; CMP- [4,5,6,7,8,9 Mononuclear leukocytes and granulocytes were isolated from human blood of normal donors by the Ficoll-Hypaque and dextran sedimentation methods (12). The mononuclear leukocytes were further fractionated using baby hamster kidney microexudate-coated flasks according to Ackerman and Douglas (13).…”

“…It acts as an inflammatory agent (2) and induces several responses representative of many critical biological reactions occurring in mammalian cells (3,4). These include stimulation of macromolecular biosynthesis, induction of certain enzymes, and alteration of plasma membrane function.…”

Inhibition of glycolysis attenuates 4-hydroxynonenal-dependent autophagy and exacerbates apoptosis in differentiated SH-SY5Y neuroblastoma cells

“…45 Under certain conditions it has been reported that 2DG could also rescue cells from oxidative stress-induced cell death. [45][46][47] However, whether 2DG effects in differentiated SH-SY5Y cells were mediated by inhibition of glycolysis, alteration of the pentose phosphate pathway and glutathione production, or attenuating glycosylation and inducing ER stress is unknown. As an alternative approach to determine if inhibition of glycolysis can alter autophagy and exacerbate HNE-induced cell death, we used a Figure 6.…”